Controlling a brightness of a lamp

Abstract

A process for controlling a brightness of a lamp includes, in at least one aspect, detecting input to control a brightness of a fluorescent lamp operated by a driving signal, and in response to detecting the input, modifying the driving signal to control the brightness of the fluorescent lamp, wherein modifying the driving signal comprises alternately applying a first duty cycle and a second duty cycle to the driving signal, wherein the first duty cycle and the second duty cycle are substantially complementary to each other.

1. A fluorescent lamp control process comprising:
 detecting input to control a brightness of a fluorescent lamp operated by a driving signal; and 
 in response to detecting the input, modifying the driving signal to control the brightness of the fluorescent lamp, 
 wherein modifying the driving signal comprises alternately applying a first duty cycle and a second duty cycle to the driving signal, wherein the first duty cycle and the second duty cycle are substantially complementary to each other. 
 
     
     
       2. The process of  claim 1 , wherein the second duty cycle is more than twice the first duty cycle. 
     
     
       3. The process of  claim 1 , wherein modifying the driving signal further comprises modifying a frequency at which the first duty cycle and the second duty cycle are applied to the driving signal. 
     
     
       4. The process of  claim 1 , wherein:
 modifying the driving signal comprises generating the driving signal by applying the first duty cycle and the second duty cycle to a first control signal and a second control signal, respectively, and 
 alternately applying the first duty cycle to the second control signal and the second duty cycle to the first control signal. 
 
     
     
       5. The process of  claim 4 , wherein modifying the driving signal further comprises modifying a frequency at which the first duty cycle and the second duty cycle are applied. 
     
     
       6. The process of  claim 4 , wherein modifying the driving signal further comprises simultaneously modifying the first duty cycle and the second duty cycle while substantially maintaining a complementarity of the first duty cycle and the second duty cycle. 
     
     
       7. The process of  claim 6 , wherein modifying the first duty cycle comprises increasing the first duty cycle and modifying the second duty cycle comprises decreasing the second duty cycle. 
     
     
       8. The process of  claim 1 , wherein a summation of the complementary duty cycles represents substantially 100% of an operating duty cycle of the driving signal, and wherein the driving signal is modified by pulse width modulation. 
     
     
       9. A fluorescent lamp control circuit configured to perform operations comprising:
 detecting input to control a brightness of a fluorescent lamp operated by a driving signal; and 
 in response to detecting the input, modifying the driving signal to control the brightness of the fluorescent lamp, 
 wherein modifying the driving signal comprises alternately applying a first duty cycle and a second duty cycle to the driving signal, wherein the first duty cycle and the second duty cycle are substantially complementary to each other. 
 
     
     
       10. The circuit of  claim 9 , wherein the second duty cycle is more than twice the first duty cycle. 
     
     
       11. The circuit of  claim 9 , wherein modifying the driving signal further comprises modifying a frequency at which the first duty cycle and the second duty cycle are applied to the driving signal. 
     
     
       12. The circuit of  claim 9 , wherein:
 modifying the driving signal comprises generating the driving signal by applying the first duty cycle and the second duty cycle to a first control signal and a second control signal, respectively, and 
 alternately applying the first duty cycle to the second control signal and the second duty cycle to the first control signal. 
 
     
     
       13. The circuit of  claim 12 , wherein modifying the driving signal further comprises modifying a frequency at which the first duty cycle and the second duty cycle are applied. 
     
     
       14. The circuit of  claim 12 , wherein modifying the driving signal further comprises simultaneously modifying the first duty cycle and the second duty cycle while substantially maintaining a complementarity of the first duty cycle and the second duty cycle. 
     
     
       15. The circuit of  claim 14 , wherein modifying the first duty cycle comprises increasing the first duty cycle and modifying the second duty cycle comprises decreasing the second duty cycle. 
     
     
       16. The circuit of  claim 9 , wherein a summation of the complementary duty cycles represents substantially 100% of an operating duty cycle of the driving signal, and wherein the driving signal is modified by pulse width modulation. 
     
     
       17. A system comprising:
 two switching elements for coupling with two fluorescent lamps, respectively; 
 
       a source to operate the two fluorescent lamps by providing a driving signal via the two switching elements; and
 a circuit configured to control a supply of the driving signal to the two fluorescent lamps, the circuit configured to perform operations comprising: 
 detecting input to control a brightness of the two fluorescent lamps operated by the driving signal; and 
 in response to detecting the input, modifying the driving signal to control the brightness of the two fluorescent lamps, 
 wherein modifying the driving signal comprises alternately applying a first duty cycle and a second duty cycle to the driving signal, wherein the first duty cycle and the second duty cycle are substantially complementary to each other. 
 
     
     
       18. The system of  claim 17 , wherein:
 modifying the driving signal comprises generating the driving signal by applying the first duty cycle and the second duty cycle to a first control signal and a second control signal, respectively; and 
 alternately applying the first duty cycle to the second control signal and the second duty cycle to the first control signal. 
 
     
     
       19. The system of  claim 17 , wherein modifying the driving signal further comprises modifying a frequency at which the first duty cycle and the second duty cycle are applied. 
     
     
       20. The system of  claim 17 , wherein modifying the driving signal further comprises simultaneously modifying the first duty cycle and the second duty cycle while substantially maintaining a complementarity of the first duty cycle and the second duty cycle. 
     
     
       21. The process of  claim 1 , wherein modifying the driving signal further comprises alternately applying only the first duty cycle and the second duty cycle to the driving signal.